Form tie



Nov. 30, 1937. x T. SCHENK 2,160,614

FORM TIE Filed Jan. 14, 1937 lNyENToR ATTORNEY Patented Nov. 30, 1937 UNITED STATES FORM TIE Tamis C. Schenk, Brooklyn, N. 'Y., assignor to Richmond Screw Anchor 00., Inc., Brooklyn, N. Y., a corporation of New York Application January 14, 1937, Serial No. 120,589

1 Claim.

This invention relates to an improvement in form ties for concrete construction and has for its object to provide a simple form tie which will be cheap to construct, easy to use, and entirely satisfactory in service.

The tie to which the invention relates is particularly intended for use inconnection with massive concrete structures wherein it is impossible, or at least not practicable, to erect the form boards for the complete height of the structure, so that the concrete structure is accordingly poured in sections and when one poured section thereof has hardened, the form boards are upwardly shifted to a position to receive the pouring of concrete for the next part of the structure.

The main object of the invention, therefore, is to provide a form tie or form support intended to be embedded in the concrete and provided with threads for the reception of lag screws which hold the form boards in position. With my improved device a very secure support for the lag screws is provided permitting the form boards to be shifted to a new position even while the concrete is green" or not fully set, yet capable of supporting the form boards in their new raised position without causing breakage or destruction of the previously poured concrete.

A further object of the invention is to provide a form tie which includes an anchorage for a form board lag screw so arranged that the screwcan engage the embedded anchorage near the face of the poured concrete so that relatively little concrete will engage the threaded shank or body of the lag screw to thereby resist its removal after the concrete has hardened.

These and other objects are attained by the invention, a more particular description of which will appear hereafter.

Reference is to be had to the accompanying drawing in which, Fig. 1 is a sectional view through a part of aconcrete structure showing the form boards at one side thereof raised and in position to receive the next pouring; and Fig.

2 is a perspective view of the tie which remains embedded in the concrete structure for the subsequent support of the form in its raised posi- 'tion.

With reference to the structure of Fig. 1, 3 indicates a plurality of connected form boards extending longitudinally and reinforced by the vertically extending upright beams 4 and longitudinally extending beams 5 and 6. In making massive concrete structures, the distance between one face as indicated at 1 of the concrete structure, and the opposite face of the same .is so great that it is not practicable to connect the form boards by connecting rods or braces extending between the two sets of the form boards. Accordingly, in structures of this kind, diagonal 6 braces such as shown at 8, may be employed. At one end, each brace is 'formed with a hook 9 which embeds in the concrete and is adjustable in the brace rod 8, and at the other end the rod is provided with a threaded portion in which en- 10 gages the form boards and supports the same. The structure just described forms no part of the present invention.

In structures of this kind, the form boards must be moved upwardly as the pouring progresses l5 and, each form board section is provided near its upper and lower end with a plurality of anchorage members 20 such as shown in Fig. 2. Each of said members consists of a pair of substantially U-shaped loops H placed in substan- 20 tially parallel relationship and having a helix l2 disposed between and welded or otherwise secured to the legs or extremities on the loops II. The helix comprises a single section of spirally wound rod. The loop members H are of sub- 25 stantial length and the helix I2 attached thereto forms threads to receive a lag screw l3 which extends through the form board structure, as shown in Fig. 1.

When one section of the concrete structure 30 has been poured, as has been done in the structure shown in Fig. l, and the concrete has hardened for a relatively short time, the form board structure is then removed and elevated and the lower portion thereof has its lag screws l4 en- 35 gaged with the anchorage member 20 embedded in and near the top of the concrete structure. The next pouring then takes place and when the concrete thus poured has hardened, the form boards are again raised and supported by the 49 anchorages which remain embedded in the concrete. The loop members H are of such length and shape that they engage about a relatively large mass of concrete and thus able -to carry the weight of the form board structure without 45 causing breakage of the concrete despite the fact that when the form board structure is raised to a position to be supported on said members, the concrete is relatively fresh or green. It will also be noted that the helix l2, forming a part 50 of the anchorage member is located very close to the face -I of the poured concrete structure, so that very little of the concrete actually engages the threads on the lag screws l3 and M. The result is that it is relatively,- easy to remove 55 the lag screws after the concrete has hardened.- This is not true of the various other types of anchorages which have heretofore been used and in which a. substantially large portion of the lag screws was actually engaged by the concrete.

While the drawing shows two loops ll of a certain elongated form, since that particularly shaped loop has been found decidedly efilcient for its intended purpose, these loops may nevertheless be increased or decreased in number and may be made in various forms and shapes to suit difierent requirements, as will be clearly understood by those skilled in this art.

What I claim is:

"in substantial alignment, said members entering into the concrete and embracing the same, the helix being attached between the legs of said loop members.

TAMIS C. SCHENK. 

